Skip to main content

Fossil Spike2

Based on game build 714014 | Last updated: 2026-03-05

Overview​

fossil_spike2 is a projectile prefab used by the Stalker enemy. It launches upward, animates, then impacts the ground where it deals damage to nearby entities, destroys collapsible structures (e.g. walls, spikes), picks some flora, kills smaller non-locomotive targets, and throws nearby items. After impact, it spawns a static FX base (fossilspike2_base) and fades out using erosion effects. This component is implemented in the fn() constructor of the prefab and is not a standalone component class, but rather a collection of functions and behaviors embedded in the entity definition.

Usage example​

The fossil_spike2 prefab is automatically spawned by the Stalker AI and should not be manually created in most mods. However, modders can reuse its core behaviors via other prefabs by replicating the construction logic in fn().

Dependencies & tags​

Components used: combat Tags added: notarget, fossilspike, FX, NOCLICK

Properties​

No public properties. Internal state is stored directly on inst (e.g., inst.shadowsize, inst.lightvalue, inst.soundlevel, inst.task, inst.killtask, inst.basefx, inst.killed).

Main functions​

The following public methods are attached directly to the instance (inst.RestartSpike, inst.KillSpike):

RestartSpike(delay, variation, soundlevel)​

  • Description: Reschedules the spike’s launch animation with optional custom parameters. Typically called to restart the spike after pausing or interrupting it.
  • Parameters:
    • delay (number?) - Optional delay in seconds before re-launching.
    • variation (number?) - Optional spike visual variant (1–7). If nil, randomly selected. If out of range, wrapped cyclically.
    • soundlevel (number?) - Optional sound volume level passed to SoundEmitter:PlaySoundWithParams.
  • Returns: Nothing.

KillSpike()​

  • Description: Immediately terminates the spike’s active lifecycle: cancels timers, spawns erosion ash at current position, adds NOCLICK tag, and triggers fade-out via ErodeAway.
  • Parameters: None.
  • Returns: Nothing.

StartSpike(inst, variation)​

  • Description: Internal initializer. Begins animation sequence (appear), sets up periodic shadow/light updates, and registers the animover callback to OnImpact. Typically called via task delay or RestartSpike.
  • Parameters:
    • inst (Entity) - The spike entity.
    • variation (number) - Visual variant ID (1–7) to override default bone symbol.
  • Returns: Nothing.

OnImpact(inst)​

  • Description: Called when the spike lands (animover event). Triggers sound, spawns base FX, sets up final timer for KillSpike, and executes area-of-effect logic via DoDamage.
  • Parameters: inst (Entity) — the spike entity.
  • Returns: Nothing.

DoDamage(inst)​

  • Description: Computes area of effect (radius PHYSICS_RADIUS + DAMAGE_RADIUS_PADDING) and executes damage logic on nearby entities:
    • Collapsible workables (chop, dig, hammer, mine) are destroyed.
    • Stumps are removed after destruction.
    • Pickables (without intense tag) are picked.
    • Combat-capable living targets are either killed (if non-locomotive and not epic) or attacked (via DoAttack).
    • Inventory items with mine are deactivated; others are tossed upward using SpikeLaunch.
  • Parameters: inst (Entity) — the spike entity.
  • Returns: Nothing.

SpikeLaunch(inst, launcher, basespeed, startheight, startradius)​

  • Description: Applies physics velocity to an entity (inst) to simulate being launched from a source (launcher), with slight randomness to angle and speed.
  • Parameters:
    • inst (Entity) — The item/launcher target to throw.
    • launcher (Entity) — Source of launch for position reference.
    • basespeed (number) — Base launch speed.
    • startheight (number) — Initial vertical offset.
    • startradius (number) — Radius to offset launch position from source.
  • Returns: Nothing.

Events & listeners​

  • Listens to: animover — triggers OnImpact when the appear animation completes.
  • Pushes: None directly. Delegates to other prefabs via SpawnPrefab (e.g., erode_ash, fossilspike2_base), which may push their own events.